1. Field of the Invention
The present invention relates to a slip casting forming method and mold in and with which the slip of refractory powders, for example, ceramic powders, metallic powders or carbon powders is cast to produce a cast article (green body), and more particularly to a forming method and mold which are well suited to produce a cast article of complicated shape.
2. Description of the Prior Art
In case of forming, by slip casting, a hollow molding whose cavity portion has a complicated shape, that is, a molding which requires a core of complicated shape not extractible due to an inverse gradient, the removal of the core has been difficult or impossible with a conventional gypsum mold.
A prior art method pertinent to the present invention is disclosed in British Pat. No. 1482436. This method consists in that a mold is made of an organic material soluble in a solvent for a part of complicated shape, while a gypsum mold is used for a part of simple shape, and that both the molds are assembled into a desired mold. This method, however, does not take it into consideration that depending upon the geometries of a cast article, a green body (a cast article) involves a difference in density between the organic part and the gypsum part, to affect the reliability of the strength of the sintering body or to affect the dimensional accuracy of the sintering body or the job efficiency of the fabrication thereof.